Friday night I started mashing for a triple-batch partigyle, and after beginning my mash I broke my hydrometer (note to self: buy TWO next time so that I'll have a backup). Anyway, since I couldn't check my gravity, I forgot that I was still probably going to have to find some way to make some adjustments in the gravity of my batches, and having forgotten, I just boiled each batch with whatever runnings I drew from the tun. Looking back, that can only have been a huge mistake on my part because the first runnings would, of necessity, be a much higher gravity than the regular recipe without a partigyle.

Specifically, I was attempting to make a "Big Foot" clone from the first runnings; the regular recipe called for 16 pounds of 2-row for a 5-gallon batch, and I put 26 pounds in the tun. I planned on a regular beer from second runnings (1st batch-sparge), and probably a fairly weak light beer from the third runnings (2nd batch-sparge). Now I don't know WHAT I have in any of my three fermenters. By the way, I wasn't using BTP for anything other than getting water addition volumes and temps for my mashtun, since I couldn't figure out how to do a partigyle with BTP. Any thoughts on that???

Anyway, if the yeasties don't quit on me early in the high gravity carboy, and therefore adequately finish the fermentation, the only solution I can think of is to blend some of it with the weakest carboy, and put some of the weakest beer back into it. That will be extra trouble but something that it better than nothing. And of course, the fact that the gravity of my first runnings was no doubt much higher than planned, this probably affected hop utilization, although I don't know how dramatically. And if the yeast doesn't finish the job due to high alcohol, I suppose I can blend the first and third carboys into two secondaries and either let the yeast in the weak beer resume fermentation of remaining sugars in the high alcohol carboy, or add a bit of yeast if needed. I have some wine yeast available, but I don't want to use it to finish fermenting the first runnings for fear that I'll dry it out and end up with so much alcohol that it will remove paint.

Well, I'm sure I'll get drinkable beer out of this one way or the other, and it's a lesson learned the hard way. Meanwhile, it anyone can think of any other possible solutions, I'm all ears.

The math that I see most often quotes for calculating a partigyle is that, with 2 equal volume runninings, 60% of the total sugar will come out (based on your expected efficiency) with the first runnings and 40% with the second runnings.

Then, assume that the gravity you calculated as 40% was 60 % of the remaining sugar, so the final runnings would be 40/60ths of that.

I think the math should work, at least as a ballpark estimate, if you assume the efficiency that you would normally expect from a 13# bill in a 5 gallon recipe, or a 26# bill in a 10 gallon recipe.